@ThreadSafe
public class BeanProcessor
extends java.lang.Object
BeanProcessor
matches column names to bean property names
and converts ResultSet
columns into objects for those bean
properties. Subclasses should override the methods in the processing chain
to customize behavior.
This class is thread-safe.
BasicRowProcessor
Modifier and Type | Field and Description |
---|---|
protected static int |
PROPERTY_NOT_FOUND
Special array value used by
mapColumnsToProperties that
indicates there is no bean property that matches a column from a
ResultSet . |
Constructor and Description |
---|
BeanProcessor()
Constructor for BeanProcessor.
|
Modifier and Type | Method and Description |
---|---|
protected int[] |
mapColumnsToProperties(java.sql.ResultSetMetaData rsmd,
java.beans.PropertyDescriptor[] props)
The positions in the returned array represent column numbers.
|
protected java.lang.Object |
newInstance(java.lang.Class c)
Factory method that returns a new instance of the given Class.
|
protected java.lang.Object |
processColumn(java.sql.ResultSet rs,
int index,
java.lang.Class propType)
Convert a
ResultSet column into an object. |
java.lang.Object |
toBean(java.sql.ResultSet rs,
java.lang.Class type)
Convert a
ResultSet row into a JavaBean. |
java.util.List |
toBeanList(java.sql.ResultSet rs,
java.lang.Class type)
Convert a
ResultSet into a List of JavaBeans. |
protected static final int PROPERTY_NOT_FOUND
mapColumnsToProperties
that
indicates there is no bean property that matches a column from a
ResultSet
.public java.lang.Object toBean(java.sql.ResultSet rs, java.lang.Class type) throws java.sql.SQLException
ResultSet
row into a JavaBean. This
implementation uses reflection and BeanInfo
classes to
match column names to bean property names. Properties are matched to
columns based on several factors:
Primitive bean properties are set to their defaults when SQL NULL is
returned from the ResultSet
. Numeric fields are set to 0
and booleans are set to false. Object bean properties are set to
null
when SQL NULL is returned. This is the same behavior
as the ResultSet
get* methods.
rs
- ResultSet that supplies the bean datatype
- Class from which to create the bean instancejava.sql.SQLException
- if a database access error occurspublic java.util.List toBeanList(java.sql.ResultSet rs, java.lang.Class type) throws java.sql.SQLException
ResultSet
into a List
of JavaBeans.
This implementation uses reflection and BeanInfo
classes to
match column names to bean property names. Properties are matched to
columns based on several factors:
Primitive bean properties are set to their defaults when SQL NULL is
returned from the ResultSet
. Numeric fields are set to 0
and booleans are set to false. Object bean properties are set to
null
when SQL NULL is returned. This is the same behavior
as the ResultSet
get* methods.
rs
- ResultSet that supplies the bean datatype
- Class from which to create the bean instancejava.sql.SQLException
- if a database access error occursprotected java.lang.Object newInstance(java.lang.Class c) throws java.sql.SQLException
c
- The Class to create an object from.java.sql.SQLException
- if creation failed.protected int[] mapColumnsToProperties(java.sql.ResultSetMetaData rsmd, java.beans.PropertyDescriptor[] props) throws java.sql.SQLException
PropertyDescriptor[]
for the bean property that matches
the column name. If no bean property was found for a column, the
position is set to PROPERTY_NOT_FOUND
.rsmd
- The ResultSetMetaData
containing column
information.props
- The bean property descriptors.java.sql.SQLException
- if a database access error occursprotected java.lang.Object processColumn(java.sql.ResultSet rs, int index, java.lang.Class propType) throws java.sql.SQLException
ResultSet
column into an object. Simple
implementations could just call rs.getObject(index)
while
more complex implementations could perform type manipulation to match
the column's type to the bean property type.
This implementation calls the appropriate ResultSet
getter
method for the given property type to perform the type conversion. If
the property type doesn't match one of the supported
ResultSet
types, getObject
is called.
rs
- The ResultSet
currently being processed. It is
positioned on a valid row before being passed into this method.index
- The current column index being processed.propType
- The bean property type that this column needs to be
converted into.ResultSet
at the given column
index after optional type processing or null
if the column
value was SQL NULL.java.sql.SQLException
- if a database access error occurs